From US 2007/0211487 A1 a lamp assembly is known, which comprises several light emitting diodes (LEDs) each arranged inside a channel-like guiding element of a housing. The guiding elements guide the emitted light rays to a common reflector. Due to this design a sharp bright/dark-cutoff is provided, so that the risk of blinding an oncoming driver is reduced. Similarly, DE 10 2007 025 337 A1 describes an LED in a recessed cavity and a semi-parabolic reflector for shaping a front beam. DE 20 2004 010 950 U1 describes an active front lighting system with an array of guiding elements, each containing an LED dome package as light source. WO 2007/057818 describes a heat sink with a recess that accommodates the LED and also acts as a guiding element. Since the bright/dark-cutoff can only be achieved by a very precise alignment of the LED to the guiding element in these designs, an unsatisfactory bright/dark-cutoff may result from even a very minor misalignment between a replacement LED and the guiding element.
There is a permanent need to facilitate the exchange of the used LEDs without affecting the correct position of the bright/dark-cutoff.